Background: The Don Quixote of literature had a tendency to do extraordinarily stupid things without thinking them through. But people were loathe to try and stop him on account of his being a few cans short of a six pack.
2. One who is an imbecile.
A: Who the bloody hell is that nutter?
B: Oh, that's Jeremy. I always knew this would happen. Looks like he's finally gone Don Quixote on us.
A: Ahhhh yes. Well will you look at that he's just hit a windmill.
(You reply)"I totally gave you a Don Quixote with that nasty skank I fucked last night!"